Well I finally fired up the 42" oven on Saturday night, after a full week of curing, and was surprised how much wood I had to keep putting on to get the dome to temperature where it started turning white, but we did eventually get there and it was awesome.
But to my horror cracks developed in the outer layer of High Temperature Mortar (HTM). I only have a rather thin coating of HTM on the outside so wasn't to concerned, but then after looking inside up around the top of the dome, after it had turned white, I saw more cracks in there, one of the cracks seems to go from up near the top all the way down to the floor, since the oven has cooled down I have had a good look and found all the cracking is in the mortar joints only.
First question to all is, Have the cracks appeared because of the thin layer of HTM on the outside, allowing to much movement when hot?
What can I do to fix it? Can I get in the oven and chip the mortar out that is cracked and refill with poor mans mortar? Should I put a thick coat over the outside of the dome?
What to do!!!!!!!!!!!
Any suggestions welcome.....
Thanks in advance